Focus detection pixels, each including a micro-lens and a pair of photoelectric conversion units disposed to the rear of the micro-lens, are arrayed on a predetermined focal plane of a photographic lens. Via this array, a pair of image signals corresponding to a pair of images formed with a pair of focus detection light fluxes passing through an optical system are generated. The focusing condition (a defocus amount indicating the extent of defocus) for the photographic lens is determined by detecting an image shift amount (phase difference), i.e., the extent of image shift manifested by the pair of image signals. A focus detection device engaged in such an operation is known in the related art as a focus detection device adopting the split-pupil phase detection method.
Color filters in a plurality of different colors may be disposed at the focus detection pixels. In such a case, focus detection is executed in correspondence to each of the plurality of colors by detecting the image shift amount for each pair of image signals output from focus detection pixels having same-color filters (see PTL 1).